added link to date-time change summary

[SVN r17388]

index.htm

@@ -145,6 +145,9 @@
 											boost/current_function.hpp</A>, <A href="libs/utility/throw_exception.html">boost/throw_exception.hpp</A>,
 										<A href="libs/utility/checked_delete.html">boost/checked_delete.hpp</A>
 									have been documented.
+									<li>  Several fixes and small additions to the <a href="libs/date_time/doc/index.html">Date-Time Library</a> including an interface change to partial_date.  See  <a href="libs/date_time/doc/Changes.html">Date-Time Change History</a> for more details.
+									</li>
+
 									<li>
 										Many fixes and enhancements to other libraries.</li>
 								</ul>